Object: The authors investigated the usefulness of using an expandable cage strut in anterior reconstruction after osteoporotic vertebral collapse in patients with neurological deficits.
Methods: Twenty-eight patients who had undergone expandable cage strut-augmented anterior thoracolumbar reconstruction participated in a follow-up review for a mean of 4.9 years. Radiographs were reviewed for kyphosis, lateral tilt of the implant, cage subsidence, the presence of a solid fusion mass, and instrumentation failure. Changes in neurological status and visual analog scale (VAS) pain score, as well as technique-related complications, were examined. The mean angles +/- the standard deviations of kyphosis correction 4 to 6 weeks after surgery and at final follow-up examination were 10.4 +/- 7.6 degrees and 5.6 +/- 6.0 degrees, respectively. The mean subsidence of the expandable cage within the adjacent vertebrae was 2.5 +/- 3.0 mm at the final follow-up examination. Neurological improvement at the final follow up was more significant in patients with Type I (wedge-type) than Type 2 (flat-type) (p = 0.037) or Type 3 (concave-type) (p = 0.006) vertebral collapse. Follow-up VAS scores were significantly higher in patients with Type 1 than Type 3 collapse (p = 0.012). In all cases the authors observed solid union with incorporation of the cage. There were no surgery-related complications.
Conclusions: An expandable titanium cage strut seems useful in vertebral body replacement in patients with osteoporotic thoracolumbar collapse. Favorable results were obtained in cases of Type I collapse (wedge type) in which the middle and posterior columns remained comparatively intact.